Callus ofSecurinega suffruticosa, a cell line accumulates dextro Securinega alkaloids

Abstract

Investigations on callus cultures of Securinega suffruticosa indicated that the cell line of S. suffruticosa callus was able to accumulate four known Securinega alkaloids with dextro rotation but not levo rotation as reported before: virosecurinine (1), viroallosecurinine (2), 14,15-dihydrovirosecurinine (3) and ent-phyllanthidine (4). Time course studies on the growth of callus cultures were carried out. The effects of different plant growth regulators, sucrose concentrations on callus growth and virosecurinine production were also reported.

Effect of plant growth regulators on the accumulation of indolizidine alkaloids in Securinega suffruticosa callus cultures

“…In the present work, the combination of 0.5 mg l -1 IAA and 5.0 mg l -1 KIN provided the highest accumulation of S and AS among all PGR compositions tested. Positive effect on indolizidine alkaloid accumulation was also noted for NAA, confirming the results by Wysokińska (1979), Ide (1991) and Yuan et al (2007), as well as IPA whose influence on alkaloid metabolism has so far been scarcely investigated.…”

“…The influence of different combinations of the above PGRs on the growth and alkaloid content in S. suffruticosa callus was also investigated by other authors. Yuan et al (2007) found that at the constant KIN concentration, the increase in 2,4-D content resulted in slower growth rate and lower alkaloid concentration. In another study, Ide (1991) tested several compositions of 2,4-D and KIN, the best of which yielded 0.06 mg g -1 S (compared to 0.32 mg g -1 S in the present work).…”

“…In previous years, in vitro cultures of S. suffruticosa were established in order to provide an efficient and reliable source of securinega alkaloids (Wysokińska 1979;Ide et al 1986;Ide 1991;Yuan et al 2005Yuan et al , 2007Raj et al 2009Raj et al , 2015. Despite promising results in terms of alkaloid accumulation, these reports provided limited data on the influence of phytohormones on the accumulation of S and related compounds in the investigated biomasses.…”

“…Given that the biosynthesis of alkaloids in plant cell cultures is strongly affected by both the type and concentration of PGRs used (Verpoorte et al 1991), modifications of phytohormone composition can be considered a simple, yet effective tool for improving the productivity of an in vitro system. However, contrary to other alkaloid groups such as indole (Verpoorte et al 1991;van der Heijden et al 2004;Pietrosiuk et al 2007) and diterpene derivatives (Sabater-Jara et al 2010;Malik et al 2011), reports concerning the influence of exogenous PGRs on indolizidine alkaloid accumulation are rather scarce and limited to the most commonly used phytohormones like 2,4-dichlorophenoxyacetic acid (2,4-D), 1-naphthaleneacetic acid (NAA), and kinetin (KIN) (Wysokińska 1979;Ide 1991;Yuan et al 2007).…”

“…The cultures were maintained at 24 ± 1°C under a 16/8 (light/dark) photoperiod (88 ± 8 lmol m -2 s -1 , Philips TLD 35 fluorescent lamps). After 4-weeks, the calli were harvested and their growth indices (Gi) calculated as described by Yuan et al (2007). After freeze-drying (Lyovac GT2, Fin-Aqua-Santasalo-Sohlberg Co, Tuusula, Finland), the samples were evaluated for S and SA content using the previously developed HPTLC-densitometric method (Raj et al 2009).…”